PSLE Pupils in a school are put into two groups for an excursion.
13 of the pupils are in Group A and the rest in Group B.
710 of the pupils in Group A are boys. In the school,
310 of the pupils are boys. What fraction of the pupils in Group B are girls?
Group A |
Group B |
Total |
1x10 |
2x10 |
3x10 |
|
|
10x3 |
10 u |
20 u |
30 u |
Boys |
Girls |
Boys |
Girls |
Boys |
Girls |
7 |
3 |
|
|
3x3 |
7x3 |
7 u |
3 u |
2 u |
18 u |
9 u |
21 u |
The total number of students is repeated.
Make the total number of students the same.
LCM of 3 and 10 is 30.
Number of boys in Group B
= 9 u - 7 u
= 2 u
Number of girls in Group B
= 20 u - 2 u
= 18 u
Fraction of the pupils in Group B that are girls
=
1820=
910Answer(s):
910